JPH06310077A - Focusing ion beam device - Google Patents

Abstract

PURPOSE:To judge the correctness of the moving direction of a sample by moving the sample in the same line direction and the same row direction, scanningly radiating a focusing ion beam in the moving direction and the vertical direction, and monitoring periodicity of a secondary electron detecting signal. CONSTITUTION:A moving mechanism 10 is arranged under an ion beam radiating optical system, and an ion beam 8 focused by the optical system is radiated to a sample 9 held by the mechanism 10. When bits of the sample 9 are arranged regularly like a matrix, the sample 9 is moved in the row direction and the column direction, and the beam 8 is radiated while scanning repeatedly in the moving direction and the vertical direction. A secondary electron from the sample 9 is detected by a secondary electron detector 7, and a detecting signal is monitored on a display device 16. When the moving direction of the sample 9 is put in the row direction and the column direction, periodicity of the detecting signal is kept, but when the moving direction is deviated, periodicity of a change in the detecting signal is broken. Thereby, the correctness of the moving direction of the sample can be judged.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a focused ion beam apparatus, and more particularly to a focused ion beam apparatus suitable for fine processing and defect analysis of a material having a regular periodic array structure on the surface such as a memory element. It is a thing.

[0002]

2. Description of the Related Art Focused ion beam devices are generally known as devices for finely processing various materials. Recently, its usefulness has been highly evaluated as a device for analyzing a defective bit of a semiconductor memory device, for example.

In the defective bit analysis of a semiconductor memory element by such a focused ion beam apparatus, first, a defective portion of a defective memory element is electrically identified at a bit level which is a memory unit. When the position information of the defective bit is found, the defective memory element is set on the movable sample stage of the focused ion beam device, and the defective bit portion of the memory element is set by the focused ion beam device. A moving operation for position adjustment is performed with respect to the sample stage so that the sample stage comes to the processing position. Then, after the defective bit portion is set at the focused ion beam processing position, the focused ion beam is irradiated to the defective bit portion, the defective bit portion is cross-section processed, and the defect is analyzed.

In the defective bit analysis of the memory element by the focused ion beam apparatus as described above, it is indispensable for the operation of the apparatus to accurately move the defective bit portion to the processing position of the focused ion beam. In the conventional focused ion beam apparatus, the moving operation for position adjustment is manually performed by the operator. Further, as a method of reducing human operation, a method of marking on the sample at an arbitrary interval, a method of detecting a repeating structure by detecting a periodic repeating structure on the sample, and controlling a transfer charge of the sample at the repeating interval Is proposed.

As a means for efficiently performing a moving operation for position adjustment, a focused ion beam apparatus disclosed in Japanese Patent Application No. 3-224348 has been proposed. It should be noted that although there is little relation to the present invention, as a positioning technique for similar position adjustment, for example, a device processing alignment device using a focused ion beam disclosed in JP-A-2-24949, There is a sample position display device of a charged particle beam device disclosed in Japanese Patent Laid-Open No. 58-75749.

[0006]

In the above-mentioned prior art, during the moving operation for moving the defective bit to the processing position of the focused ion beam, it is determined whether the actual moving direction of the sample maintains the intended moving direction on the sample. There was no consideration for confirmation, and it did not meet the market demand for higher reliability.

An object of the present invention is to provide a focused ion beam apparatus capable of improving reliability by determining whether or not the moving direction is correct during the moving operation for moving the defective bit to the processing position of the focused ion beam. It is in providing.

[0008]

The focused ion beam apparatus according to the present invention is configured as follows in order to achieve the above object.

As is known, the focused ion beam apparatus according to the present invention is an ion beam irradiation optical system for deflecting and irradiating a focused ion beam on a sample, a sample moving mechanism for holding and moving the sample, and this sample. A moving amount detecting means for detecting a moving amount by a moving mechanism, a charged particle detecting means for detecting charged particles emitted from a sample by ion beam irradiation by an ion beam irradiation optical system, deflection control of a focused ion beam, and movement of the sample It has a control processing means for controlling and storing and processing the charged particle detection signal, and a display means for displaying the surface state of the sample. Further, when a repetitive shape having a predetermined interval is present on the surface of the sample, the periodicity and the waveform of the change of the detection signal output by the charged particle detecting means and having the periodic change corresponding to the repetitive shape change are maintained. A periodicity determining means for determining whether or not the sample is moved is configured to move the sample while repeatedly scanning the focused ion beam in a direction perpendicular to the moving direction of the sample. The periodicity determination means is included in the control processing device.

In the above structure, the operator sets a target position for movement and controls the sample moving mechanism based on the moving amount and the moving direction to automatically move the sample. At this time, the period of the charged particle detection signal is changed. It is configured to determine the correctness of the moving direction according to the sex and the waveform.

More preferably, a means for irradiating the surface of the sample with light and a means for receiving and detecting the reflected light are additionally provided,
Alternatively, a scanning tunnel electron microscope is additionally provided, and the detection output of these devices is used in place of the output of the charged particle detection means to determine the movement of the sample and the correctness of the movement direction.

[0012]

In the focused ion beam apparatus according to the present invention, the fact that the bits of the memory elements are regularly arranged in a matrix like a matrix is utilized when the defective bits of the semiconductor memory element are analyzed. , The sample is moved in the same direction and in the same column. During movement of the sample, the focused ion beam is irradiated while repeatedly scanning in the direction perpendicular to the moving direction of the sample, and the charged particle detection signal is monitored. If the moving direction of the sample is the same direction or the same column direction, the periodicity of the change of the charged particle detection signal is maintained, and if the moving direction of the sample deviates from the same direction or the same column direction, the change cycle of the charged particle detection signal concerned Since the property deteriorates, it is possible to determine whether the moving direction of the sample is kept in the same direction or the same column direction.

In the focused ion beam device according to the present invention,
As described above, it is possible to monitor whether the moving direction of the sample is kept in the direction intended by the operator while moving the sample,
The reliability of sample movement can be improved.

[0014]

Embodiments of the present invention will be described below with reference to FIGS.

FIG. 1 is a diagram showing the overall structure of a focused ion beam apparatus according to the first embodiment of the present invention. Vacuum container 1
The inside of the is vacuum-exhausted by an exhaust device (not shown). The ion beam irradiation optical system is installed in this vacuum container 1, and is composed of an ion source 2, an extraction electrode 3, a condenser lens 4, a deflection electrode 5, and an objective lens 6. A moving mechanism 10 that moves the sample 9 is installed below the ion beam irradiation optical system, and the sample 9 held by the moving mechanism 10 is irradiated with the ion beam 8 focused by the ion beam irradiation optical system. At this time, the secondary electrons emitted from the sample 9 are detected by the secondary electron detector 7.

Each of the above-mentioned components of the ion beam irradiation optical system is further provided with an ion source power source 11, a lens power source 12, and a deflection power source 13, and power is supplied to the corresponding components. Each output of the ion source power source 11, the lens power source 12, and the deflection power source 13 is controlled by the control processing unit 17. The moving mechanism 10 is driven by being supplied with power from the moving mechanism power supply 14, and its control is performed by the control processing unit 17.

Input / output control of the secondary electron detector 7 is performed by the detector power supply 15, and the detection signal output from the secondary electron detector 7 is sent to the control processing unit 17 via the detector power supply 15. To be Information on the state of the apparatus and the state of the surface of the sample 9 is sent from the control processing unit 17 to the display device 16 and displayed as an image. Imaging of the surface state of the sample 9 is performed based on the signal output from the secondary electron detector 7.

An example of the operation of displaying the surface condition of the sample 9 on the display device 16 by the focused ion beam device having the above structure will be described.

The sample 9 is placed and held on the stage of the moving mechanism 10. First, the ion beam 8 is generated from the ion source 2 and irradiated on the sample 9. At this time, the ion beam 8 is narrowed down by adjusting the voltage applied to the extraction electrode 3, the condenser lens 4, and the objective lens 6. The voltage applied to the deflection electrode 5 is a sawtooth wave, and this voltage causes the ion beam 8 to scan the surface of the sample 9. At this time, the moving mechanism 10 does not operate, and the sample 9 is in a stopped state.
The control signal of the voltage applied to the deflection electrode 5 is used as the scanning signal of the display device 16. The detection signal output from the secondary electron detector 7 is used as the luminance signal of the display device 16. Thus, using the control signal of the voltage applied to the deflection electrode 5 and the detection signal output from the secondary electron detector 7, the state of a partial region on the surface of the sample 9 is displayed by the display device 16.
Is displayed in. When observing the surface of the semiconductor memory element with a focused ion beam apparatus based on such display operation, it is necessary to observe an array structure having regularity, that is, periodicity of bits by contrast due to a change in a detection signal corresponding to unevenness of each bit. You can

The relationship between the surface of the sample 9 and the detection signal of the secondary electron detector 7 in the above case will be described in detail with reference to FIG. In the following description, the sample 9 is assumed to be a semiconductor memory device.

FIG. 2A is an image of the surface of the sample 9,
The solid part of the solid line indicates the bright part, the coarse part of the solid line indicates the dark part, and the other parts indicate the part with no change in brightness. The image of the surface of sample 9 shows each of a number of bit components because the sample is a semiconductor memory device. The surface of the sample 9 formed of a large number of bit components shows a pattern of a periodic array structure. Figure 2 (A)
2B shows a cross-sectional structure taken along line AA ′ in FIG. 2, and detection by the secondary electron detector 7 when the ion beam 8 is scanned along line AA ′ in FIG. FIG. 2C shows the state of the signal.

FIG. 2 (B) shows three bit component parts 18 which are memory units in the semiconductor memory device. As shown in FIG. 2B, the surface of the sample 9 that is a memory element has unevenness for each bit component portion 18, and the unevenness of the detection signal also causes a change as shown in FIG. 2C according to the unevenness. Has occurred.

Note that FIG. 2A shows the end of the array of bit constituent parts, and the bit constituent part at the intersection of the AA 'line and the BB' line is the first bit. Has become. The bit portion at the end, which is determined as the intersection of the line AA 'and the line BB', is used as a reference point. The reference point has a function as a movement start point when the movement is performed as described later by using the focused ion beam device.

Next, during movement of the sample, the surface of the sample 9 and the secondary electron detector 7 when the sample is moved while being irradiated with a focused ion beam so as to repeatedly scan in a direction perpendicular to the moving direction of the sample. The relationship with the detection signal of will be described with reference to FIG.

FIG. 3A shows the surface of the bit forming portion of the sample 9 and the locus of the ion beam 8. X-X1
The line indicates the moving direction when the sample 9 moves in the same column direction of the bit configuration with X ₀ as the starting point (reference point), and is X-X2.
The line shows an example of the moving direction of the sample 9 when the sample 9 moves out of the same row direction of the bit configuration with X ₀ as the starting point (reference point). The triangular wave line superimposed on the X-X2 line indicates the trajectory of the ion beam 8 when the moving direction of the sample 9 is the X-X2 line. FIG. 3B shows X of sample 9.
The cross-sectional shape along line -X1 is shown and corresponds to FIG. FIG. 3C shows the relationship between the detection signal intensity of the secondary electron detector 7 and the movement amount of the sample 9 when the ion beam 8 passes from X ₀ to X ₁ shown in FIG. 3A. The solid line
This is the detection signal strength of the secondary electron detector 7. The broken line shows a setting example of the allowable range for variations in the detected signal strength. In FIG. 3D, the ion beam 8 is shown in FIG.
The relationship between the detection signal intensity of the secondary electron detector 7 and the amount of movement of the sample 9 when passing from X ₂ to X ₃ shown in FIG. The solid line represents the detection signal intensity of the secondary electron detector 7. The broken line is
The broken line shown in FIG. 3C is moved and shown.

When the moving direction of the sample 9 is the same row direction (along the line XX-1), the detection signal of the secondary electron detector 7 is the repetition of FIG. The pattern has a periodicity similar to that of C). Further, when the ion beam 8 is scanned along the line X-X1 from X ₀ to X ₁ while the moving mechanism 10 is not operated and the sample 9 is stopped, the same pattern detection as in FIG. 3C is performed. The signal is obtained. When the moving direction of the sample 9 deviates from the same direction (X
(Along the −X2 line), the detection signal of the secondary electron detector 7 is sometimes as shown in FIG.
As in (D), there is no periodicity.

The determination as to whether or not the periodicity is maintained by the above detection signal is actually performed by the periodicity determination means which is realized by being software-embedded in the control processing unit 17 having a data processing function. . Whether or not there is periodicity is determined based on the reference waveform and the allowable deviation amount from the reference waveform. The reference waveform is shown in FIG. The allowable shift amount is set according to the reliability required by the operator based on the reference waveform, and is the amount shown by the broken line in FIG. 3 (C). The periodicity determination means is equivalent to the reference waveform by identifying whether or not the state of change of the detection signal of the secondary electron detector 7 collected during the movement of the sample is within the allowable deviation amount described above. It is determined whether or not

Next, an operation example in which the above focused ion beam apparatus is used for defective bit analysis of a semiconductor memory element will be described.

Sample 9 is a semiconductor memory device. In this semiconductor memory device, the defective bit portion, which is the target position for movement, is electrically obtained with other positional information by other means. From the calculated position information,
With the intersection of the AA 'line and the BB' line shown in (A) as a reference point, the movement amount in the AA 'line direction and the BB' line direction is
It is obtained as movement amount data regarding the target position.

In the above state, the sample 9 is placed on the stage of the moving mechanism 10 of the focused ion beam apparatus. This state is shown in FIG. As described with reference to FIGS. 1, 2 and 3, the moving mechanism 1 of the focused ion beam apparatus is described.
With the sample 9 placed at 0, the ion beam is scanned to determine the reference point, and the reference waveform is obtained. The reference point is A-
It is the intersection of the line A'and the line BB ', which is the leftmost bit forming portion of the semiconductor memory device in FIG. A part of the sample 9 shown in FIG. 2A is displayed on the display device 16 having a monitor function. In the display image of the display device 16, the reference point of the sample 9 is clearly grasped. The reference waveform is shown in FIG. The reference waveform is obtained by sweeping the ion beam from X ₀ to X ₁ along the solid line in FIG. Or, while sweeping the ion beam in the longitudinal direction at the X _0, a waveform equivalent can be obtained by moving the sample 9 from X ₀ to X _1. An allowable deviation amount is set for the obtained reference waveform.

Next, the movement is performed. The first move is to the reference point. The reference point is the intersection of the line AA 'and the line BB'. The position of the sample 9 is moved so that the reference point comes to the center of the scanning region of the ion beam 8. The movement of the sample 9 is
This is performed with reference to the display image on the display device 16. Next, the movement to the target position is performed. The movement data to the target position includes the above-mentioned AA ′ line direction from the reference point and BB ′.
Use the amount of linear movement. First, it moves in the direction of the line AA '. While moving, the control processing unit 17 collects the detection signal of the secondary electron detector 7 while repeatedly sweeping the ion beam 8 in the BB ′ line direction. At the same time, the control processing unit 17 collects the moving amount of the sample 9 by the moving mechanism 10. In the control processing unit 17, every time the amount of movement of the sample becomes 1 bit, the periodicity determination means determines whether or not it can be regarded as equivalent to the reference waveform. When it is judged that the waveform is different from the reference waveform, the movement is stopped and the operation returns to the reference point. If all are judged to be equivalent to the reference waveform, the process moves to the line BB 'direction. While moving, the control processing unit 17 collects the detection signal of the secondary electron detector 7 while repeatedly sweeping the ion beam 8 in the AA ′ line direction. At the same time, the control processing unit 17 collects the moving amount of the sample 9 by the moving mechanism 10. In the control processing unit 17, each time the sample movement amount is 1 bit,
The periodicity determining means determines whether or not the waveform can be regarded as equivalent to the reference waveform. When it is judged that the waveform is different from the reference waveform, the movement is stopped and the operation returns to the reference point. When it is determined that they are all equivalent to the reference waveform, the position where the movement has ended is the target position.

In the above embodiments, the detection signal of the secondary electron detector 7 is treated as one-dimensional information, but the detection signal is
Essentially, it is information that is distributed in two dimensions on the sample surface.
Therefore, by providing the periodicity determining means for processing the detection signal as two-dimensional information, when the movement direction of the sample deviates from the same column direction or the same direction, the deviation direction can be discriminated.

An example of a determination method for processing the detection signal of the secondary electron detector 7 as two-dimensional information will be described below with reference to FIG. FIG. 4A shows the surface of the bit forming portion of the sample 9 and the trajectory of the ion beam 8. The ab line shows the trajectory of the ion beam 8 when the sample 9 moves in the same row direction of the bit configuration with X ₀ as the starting point (reference point),
The a-c line shows an example of the locus of the ion beam 8 when the sample 9 moves out of the same row direction of the bit configuration with X ₀ as the starting point (reference point). FIG. 4B shows the detection signal intensity of the secondary electron detector 7 and the movement amount of the sample 9 indicated by a circle when the ion beam 8 passes from a to b shown in FIG. 4A. Shows the relationship. FIG. 4C shows
When the ion beam 8 passes from a to c shown in FIG. 4 (A) and the detection signal intensity (solid line) of the secondary electron detector 7 shown by a triangle, when passing from a to c The relationship between the detection signal intensity (broken line) of the secondary electron detector 7 and the amount of movement of the sample 9 is indicated by the triangle. Figure 4 (D)
Is the detection signal intensity (solid line) of the secondary electron detector 7 at the place indicated by the square when the ion beam 8 passes from a to b shown in FIG. The relationship between the detection signal intensity of the secondary electron detector 7 (broken line) and the amount of movement of the sample 9 at the place indicated by a square at the time of is shown. Figure 4
2B has a waveform similar to that of FIG. Figure 4 (C)
Then, as compared with the waveform (solid line) in the case of ab line, the waveform (dashed line) in the ac line is initially high and lower in the latter half. In FIG. 4D, the waveform (broken line) on the a-c line is lower at the beginning and higher in the latter half than the waveform (solid line) in the case of the a-b line. The deviation in the moving direction of the sample is shown in Fig. 4 (A).
In the case opposite to the line a-c shown by, the changes in FIGS. 4C and 4D are also reversed. Therefore, the detection signals of the secondary electron detector 7 are collected at three points of circle, triangle and square, the periodicity is judged by the data at the circle, and the level change is checked by the data at the triangle and square points. By doing so, it is possible to judge whether or not the moving direction of the sample is deviated, and the deviating direction when it is deviated. According to this determination means, since the direction of deviation can be known, the direction of movement of the sample can be corrected when the direction of movement begins to deviate. Furthermore, image information is created from the scanning control signal of the ion beam 8, the control signal of the sample movement, and the detection signal of the secondary electron detector 7, and it is judged by image recognition whether the moving direction of the sample is correct or not. You can also do it.

As described above, the position of the defective bit portion in the semiconductor memory device can be electrically grasped in advance, and based on this, the sample 9 is moved by using the moving mechanism 10 in the same column direction and the same row direction. By moving, the defective bit portion can be surely moved to the center of the scanning region which is the processing position of the ion beam 8. After the movement is completed, the irradiation position of the ion beam 8 is the target position on the sample 9, that is, the defective bit portion. Therefore, the ion beam 8 can be used to perform necessary processing on a defective bit portion of the semiconductor memory element, that is, a portion requiring processing.

Next, a second embodiment of the present invention will be described with reference to FIG. FIG. 5 is configured by adding a light source 19, a light receiving detector 21, and a light receiving detector power source 22 to the configuration of FIG.
Light 20 narrowed down from the light source 19 corresponding to the bit width is applied to the surface of the sample 9, and the reflected light is received by the light receiving detector 21. The signal from the light receiving detector 21 is supplied to the light receiving detector power supply 22.
A / D conversion is performed by the control processing unit 1 as digital data.
Send to 7. Here, the irradiation position of the light from the light source 19 is set near the fixed position of the ion beam 8. Sample 9
When is moved, a signal similar to that shown in FIG.
Therefore, regarding the reference waveform and the moving waveform, the signal of the light receiving detector 21 is used instead of the signal from the charged particle detector 7 described in the description of the embodiment with reference to FIG. In this way, the same operation as described with reference to FIG. 1 can be performed for grasping the moving direction of the sample. Further, according to the present embodiment, it is not necessary to irradiate the sample 9 with the ion beam 8 during the movement of the sample, so that the voltage applied to the deflection electrode 5 is changed so that the ion beam 8 does not hit the sample 9. , It is possible to prevent the sample surface from being damaged.

Next, a third embodiment of the present invention will be described with reference to FIG. FIG. 6 is configured by additionally providing a probe drive unit 23 and a control unit 24 of the scanning tunneling microscope to the configuration of FIG. It is assumed that the probe of the probe drive unit 23 is set near the scanning region of the ion beam 8. When the sample 9 is moved, it is possible to obtain information on the height that changes according to the unevenness of the sample 9. This information can be used in place of the signal from the charged particle detector 7 described in the description of the embodiment with reference to FIG. 1, and the same operation as described with reference to FIG. 1 can be performed for grasping the moving direction of the sample. it can. Further, according to the present embodiment, it is not necessary to irradiate the sample with the ion beam 8 while the sample is moving, so that the voltage applied to the deflection electrode 5 is changed so that the ion beam 8 does not hit the sample. The surface can be protected from damage.

[0037]

According to the present invention, when a sample having a regular array structure such as a bit array of a semiconductor memory device is moved, the moving direction of the sample is surely set to the same direction and the same column direction of the array structure. By doing so, the sample can be moved accurately, and the operation efficiency can be improved.

By using the received light detection signal or the tunnel current detection signal instead of the charged particle detection signal, it is not necessary to irradiate the sample with the ion beam during the movement of the sample, so that the sample surface is damaged. You can prevent them from suffering.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a focused ion beam device according to a first embodiment of the present invention.

FIG. 2 is a diagram showing a relationship between a surface and a cross section of a sample (in the case of a memory element) and a detection signal.

FIG. 3 is a view showing a relationship between a surface and a cross section of a sample (in the case of a memory element) and a detection signal.

FIG. 4 is a diagram showing a relationship between a surface of a sample (in the case of a memory element) and a detection signal.

FIG. 5 is a configuration diagram of a focused ion beam device according to a second embodiment of the present invention.

FIG. 6 is a configuration diagram of a focused ion beam device according to a third embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Vacuum container, 2 ... Ion source, 3 ... Extraction electrode, 4 ... Condenser lens, 5 ... Deflection electrode, 6 ... Objective lens, 7 ...
Secondary electron detector, 8 ... Ion beam, 9 ... Sample, 10 ...
Moving mechanism, 11 ... Ion source power supply, 12 ... Lens power supply, 1
3 ... Deflection power supply, 14 ... Moving mechanism power supply, 15 ... Detector power supply, 16 ... Display device, 17 ... Control processing part, 18 ... Bit component part, 19 ... Light source, 20 ... Light from light source, 21 ...
Light receiving detector, 22 ... Light receiving detector power source, 23 ... Probe driving unit of scanning tunneling microscope, 24 ... Control unit of scanning tunneling microscope.

Claims (3)

[Claims] 1. An ion beam irradiation optical system for deflecting a focused ion beam to irradiate a sample, a sample moving mechanism for holding and moving the sample, and a moving amount detecting means for detecting a moving amount by the sample moving mechanism, Charged particle detecting means for detecting charged particles emitted from a sample by ion beam irradiation by an ion beam irradiation optical system, control processing for deflection control of a focused ion beam, sample position control, and storage and processing of a charged particle detection signal. In the focused ion beam apparatus having a means and a display means for displaying the surface condition of the sample, when the sample surface has a repetitive shape with a predetermined interval, the charged particle detection means outputs and responds to the repetitive shape change. During the movement of the sample, it has a periodicity determination means for determining whether or not the periodicity or the waveform of the change of the detection signal having the periodical change is maintained. The sample is moved while irradiating the sample with a focused ion beam so as to be repeatedly scanned in the direction perpendicular to the moving direction of the sample, and at this time, the periodicity or waveform of the change of the detection signal output by the charged particle detection means is maintained. The focused ion beam device is characterized by determining whether or not the moving direction of the sample is correct depending on whether the sample is moving or not. 2. The focused ion beam device according to claim 1, further comprising means for irradiating the surface of the sample with light and means for receiving and detecting the reflected light thereof, and these means are provided in place of the charged particle detecting means. Using the method, the sample is moved while repeatedly changing the direction of the irradiation light in the direction perpendicular to the moving direction of the sample, and the periodicity of the change in the detection signal output by the means that receives and detects the reflected light at this time. Alternatively, the focused ion beam device is characterized in that whether or not the moving direction of the sample is correct is determined depending on whether or not the waveform is maintained. 3. The focused ion beam apparatus according to claim 1, wherein a scanning tunnel electron microscope is additionally provided, the scanning tunnel microscope is used in place of the charged particle detecting means, and the scanning tunnel microscope is used to move a sample. The sample is moved while repeatedly repeatedly moving in the direction perpendicular to the direction, and at this time, whether the sample moving direction is correct or not depends on whether the periodicity or the waveform of the change in the output of the scanning tunneling microscope is maintained. A focused ion beam device characterized by determining whether or not.